Single-Molecule Resolved Conformational and Orbital Symmetry Breaking in Tetraphenylethylene-Based Macrocycles
Tetraphenylethylene (TPE) is a prototype aggregate-induced emission molecule. TPE-based conjugated macrocycles exhibit unique optical properties due to their peculiar cyclic topology. Because the symmetry of macrocycles strongly affects their photophysical properties, here we report a single-molecule study of the structures and orbitals of two TPE-based macrocycles of (C<sub>26</sub>H<sub>18</sub>)<sub>4</sub> and (C<sub>26</sub>H<sub>18</sub>)<sub>6</sub>. Using scanning tunneling microscopy and spectroscopy, we discover that both macrocycles undergo spontaneous symmetry breaking in their conformations and frontier orbitals. The computational analyses reveal that the symmetry breaking is driven by a subtle interplay of higher extended conjugation between phenyl and node carbon atoms and conformation flexibility of the macrocycles. The observed symmetry breaking in TPE-based macrocycles is expected to strongly alter their photophysical properties.
Authors
- Jun Zhu (ORCID: https://orcid.org/0000-0002-2099-3156)
- Nian Lin (ORCID: https://orcid.org/0000-0001-5693-4011)
- Chengyi Chen (ORCID: https://orcid.org/0000-0001-9216-0551)
- Chengkun Lyu (ORCID: https://orcid.org/0000-0002-9167-6182)
- Huilin Xie (ORCID: https://orcid.org/0000-0001-6685-5464)
- Jacky W. Y. Lam (ORCID: https://orcid.org/0000-0001-5754-1703)
- Tao Lin
- Ben Zhong Tang (ORCID: https://orcid.org/0000-0002-0293-964X)
- Jianyu Zhang (ORCID: https://orcid.org/0000-0002-5213-7063)
- En Li (ORCID: https://orcid.org/0000-0001-5761-9873)
- Songshan Dai
Institutions
- Xiamen University (CN)
- Hong Kong University of Science and Technology (HK)
- Chinese University of Hong Kong, Shenzhen (CN)
- Shenzhen Technology University (CN)
- Collaborative Innovation Center of Chemistry for Energy Materials (CN)
- University of Hong Kong (HK)
Publication Details
- Journal
- Journal of the American Chemical Society
- Published
- 2024-11-29
- DOI
- https://doi.org/10.1021/jacs.4c12746
- Citations
- 9
- Primary Topic
- Luminescence and Fluorescent Materials
- Type
- article
- Field-Weighted Citation Impact
- 1.05
Funders
- Research Grants Council, University Grants Committee
- Innovation and Technology Commission